The focus of this thesis is to derive analytical tools for the design of infrared nondestructive tests in single and multi layer material bodies. This requires the predetermination of the parameters of the experiment such that the infrared image has the required resolution for defect detection. Inverse heat conduction in single and multi-layer materials is investigated to determine the required frequency of excitation in order to obtain a desired temperature at the observation point. We use analytical quadrupole representation to derive a polynomial relation to estimate the frequency of the periodic excitation as a function of the temperature amplitude at a given observation point within the body. The formula includes characteristic geometric and material parameters of the system. The polynomial formula can be an e ective design tool for quick frequency predetermination in the design of non-destructive testing experiments with infrared thermography. The convergence and accuracy of the formula is assessed by comparison with the analytical thermal quadrupole solution and experimental results. We also investigate the e ect of the nite length of the material domain in order to establish the range of applicability of a simpli ed formula based on semi-in nite domain assumption. The e ect of nite length is investigated analytically by using (i) Fourier series which accounts for transients and (ii) Time varying solution associated to the steady state solution when a purely periodic excitation is applied. These results are also compared with numerical solution obtained with commercial nite element software ANSYSTM.

This PhD thesis is concerned with developing a methodology for early diagnosis of cancer by comparing the resonant frequencies in the amplitude spectra obtained during a vibration test using the AFM or, by comparing the stiffness properties of single cancerous and normal cells obtained using a resonant technique. As there is no reliable data in the literature to prove the existence of resonant frequencies of single cells, this work pioneers the search for resonant frequencies of related microspherical soft bodies using the AFM. Experiments to investigate the resonant behaviour of single cells depends on various parameters which are difficult to control; for example, the cell type, deciding at what stage the cell should be tested during the culturing process, determining the nucleus size, determining the cytoskeleton integrity and designing an appropriate vibration test setup among others. For this reason, agarose microspheres were selected to carry out preliminary work as these samples have similar properties to human cells and their resonances are affected by fewer variables. Although these micrometric spheres were tested under different conditions, no clear resonant behaviour was found at frequencies below 20 kHz and, only wide curves (interpreted as highly damped peaks of resonance) in the interval ranging from 20 kHz to 100 kHz were observed. By considering those curves as the quadrupole (Qp) vibration mode, approximate stiffness values for the agarose microspheres were found to be in between 37 kPa and 72 kPa. These values are similar to those obtained during an indentation test performed on the same samples whic¬¬h gave Young’s modulus values ranging from 10 kPa to 200 kPa. In order to gain a greater insight into the vibration test performed on microscopic samples, the research was extended to include agarose spheres of millimetric size. The characterization of these samples was carried out using an innovative purpose-built experimental setup. For the vibration test, a PZT based excitation device and a vibro-acoustic sensor were designed and constructed. The amplitude spectra of the vibration tests performed on millimetric samples consistently showed at least three peaks of resonance from which after the numerical simulation of the vibration test were interpreted as the quadrupole (Qp) and octupole (Op) vibration modes. Using this information, stiffness values for the samples ranging from 100 kPa to 700 kPa were calculated. In order to obtain the stiffness of the millimetric samples using a different technique, an experimental setup was constructed to perform a compression test. However, due to high viscoleasticity of the samples, it was not possible to obtain a standard compression curve necessary for their mechanical characterization. The results obtained from the tests on millimetric agarose samples demonstrate that spheres made of this material are able to provide measurable vibrational characteristics. Consequently, this methodology can be further implemented on micrometric samples and possibly on human cells to detect their resonant frequencies and equivalent stiffness values which can be used as a cancer marker. From the vibrational experiments on millimetric samples, it was noticed that the excitation mechanism plays an important role and for this reason future work is proposed to continue in this direction.

This thesis discusses in general terms the theory and application of time-differential perturbed angular correlation gamma-ray spectroscopy (TDPAC) to the study of solid state physics. The technique yields valuable information on the electric field gradients experienced by radionuclides which have been substituted for nonradioactive isotopes or inserted as impurities into various inorganic compounds. The indium halides are examined in a series of experiments. The first applications of this technique to the study of graphite intercalation compounds are discussed. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Examinations of the effects of (a.) alkyl carbon chain length and (b.) perfluorination of acyl chlorides; propionyl chloride, butyryl chloride, valeroyl chloride, and perfluorinated acyl chlorides; perfluoropropionyl chloride and perfluorobutyryl chloride, are reported and compared using CP-FTMW spectroscopy. All of these molecules are already published in various journals except for valeroyl chloride. The chapters are organized by molecule alkyl chain length and include some background theory. Conformational stability, internal rotation, helicity, and ionic character of the C-Cl bond via the nuclear electric quadrupole coupling constant (χzz) are analyzed. Results show syn, syn-anti/syn-gauche, and syn-anti-anti/syn-gauche-anti stable conformations. Internal rotation was only seen in propionyl chloride. Helicity was not observed. (χzz) was observed to be inert to alkyl chain length, ~ 60 MHz and ~ 65 MHz for the nonfluorinated and fluorinated acyl chlorides. Partial fluorination and varying functional groups are recommended.

<p> Edible oils consist primarily of triacylglycerols (or TAGs), which are triesters of glycerol and fatty acids. Determination of the TAG compositions of edible oils is becoming more important, given the economic value of these oil products and the increasing incidence of adulterating high quality oils with poorer quality oils. In this study we report the development of an analytical protocol using positive ion infusion electrospray mass spectrometry (ESI/MS) in conjunction with tandem mass spectrometry which affords both identification and quantification of TAGs in edible oils samples.</p> <p> This thesis reports a simple, comprehensive and quantitative method for the analysis of TAGs in edible oils in which the optimized method involves the infusion of an oil sample in chloroform:methanol (1:1) solution (~10-15 μg/mL of oil) in the presence of 0.5 mM LiCl. A sequence of corrections were applied to the raw peak area data of the TAG molecular ions, [M+Li]+, to account for: (1) normalization of peak area data using three internal standards, (2) peak area contributions of M+2 isotopic peaks of TAGs with one more degree of unsaturation and (3) peak area contributions of LiCl adduct ions, [M+Li+LiCl]+, when applicable. The major correction involved multiplication to a given TAG peak area by the appropriate electrospray relative response factor (RRF) for that TAG. The RRFs for all TAGs containing between 48 and 63 carbons in their fatty acyl chains and between 0 and 9 degrees of unsaturation were extrapolated from experimentally determined response factors of a series of standards. The RRFs were found to decrease by 6.7% for each additional acyl chain carbon but increased by 18.6% for each double bond. Comparison of these calculated RRFs to reported RRFs for a series of TAG standards showed an excellent correlation (1.06% ± 10.20% RSD).</p> <p> The use of Li+ in TAG analysis followed from the reports by Hsu and Turk [93] and Han and Gross [18] which showed that Li+ afforded more intense MS, and particularly MS/MS, spectra than either H+ or Na+. The enhanced intensities in MS/MS spectra (determined using a triple quadrupole mass spectrometer) were critical for the identification of TAGs, including the identity of the fatty acyl group located at the sn-2 position. However, this method cannot distinguish unambiguously between isobaric TAGs. This methodology was applied to the profiling of a number of edible oils including canola, olive, sesame, grape seed, walnut and hemp seed oils. The major TAGS in these samples contained 52, 54 and 56 carbons with between 0 and 11 degrees on unsaturation in a given TAG. There were minor amounts of TAGs containing 50, 55 and 57 carbons.</p> <p> The ability of this method to determine quantitatively the number of degrees of unsaturation in an oil sample was tested by examining a series of partially hydrogenated canola oil samples kindly provided by Bunge Canada. Five oil samples derived from a single feedstock with differing numbers of degrees of unsaturation, measured as iodine values, were subjected to our analytical method. The measured iodine values were compared to iodine values calculated from the number of degrees of unsaturation obtained by our MS-based method. The slope of this correlation was 1.10 with an R^2 = 0.995. Overall, this method is much simpler and more accurate than the protocol described by Han and Gross [18]. This methodology will be applied as routine method for the analysis of TAGs in biological samples such as blood samples.</p> / Thesis / Master of Science (MSc)

A nuclear microprobe, typically consisting of 2 - 4 quadrupole magnetic lenses and apertures serving as objective and a collimating divergence slits, focuses MeV ions to approximately 1 x 1 μm for modification and analysis of materials. Although far less utilized, electrostatic quadrupole fields similarly afford strong focusing of ions and have the added benefit of doing so independent of ion mass. Instead, electrostatic quadrupole focusing exhibits energy dependence on focusing ions. A heavy ion microprobe could extend the spatial resolution of conventional microprobe techniques to masses untenable by quadrupole magnetic fields. An electrostatic quadrupole doublet focusing system has been designed and constructed using several non-conventional methods and materials for a wide range of microprobe applications. The system was modeled using the software package "Propagate Rays and Aberrations by Matrices" which quantifies system specific parameters such as demagnification and intrinsic aberrations. Direct experimental verification was obtained for several of the parameters associated with the system. Details of the project and with specific applications of the system are presented.

No description available.

<p>Conventional mass spectrometry sensing has isomorphic nature, which means measure the input mass spectrum abundance function by a resemble of delta function to avoid ambiguity. However, the delta function nature of traditional mass spectrometry sensing approach imposes trade-offs between mass resolution and throughput/mass analysis time. This dissertation proposes a new field of mass spectrometry sensing which combines both computational signal processing and hardware modification to break the above trade-offs. We introduce the concept of generalized sensing matrix/discretized forward model in mass spectrometry filed. The presence of forward model can bridge the cap between sensing system hardware design and computational sensing algorithm including compressive sensing, feature/variable selection machine learning algorithms, and stat-of-art inversion algorithms. </p><p>Throughout this dissertation, the main theme is the sensing matrix/forward model design subject to the physical constraints of varies types of mass analyzers. For quadrupole ion trap systems, we develop a new compressive and multiplexed mass analysis approach mutli Resonant Frequency Excitation (mRFE) ejection which can reduce mass analysis time by a factor 3-6 without losing mass spectra specificity for chemical classification. A new information-theoretical adaptive sensing and classification framework has proposed on quadrupole mass filter systems, and it can significantly reduces the number of measurements needed and achieve a high level of classification accuracy. Furthermore, we present a coded aperture sector mass spectrometry which can yield a order-of-magnitude throughput gain without compromising mass resolution compare to conventional single slit sector mass spectrometer.</p> / Dissertation

No description available.

No description available.